Vga_switcheroo currently invokes fb_switch_outputs() to inform fbcon
about switching of the physical outputs among framebuffer devices. But
new DRM clients to not use fbdev/fbcon and might require their own
vga_switcheroo support. Let's strictly separate them from each other.

Remove fbdev/fbcon from vga_switcheroo. Introduce a pre_switch callback
for vga_switcheroo clients to do the fbcon update. Allows for removing
all direct interactions between vga_switcheroo and fbdev/fbcon.

Also replace the existing reprobe hook with post_switch for symetry.

At the same time, push the fbcon update into DRM's client for fbdev
emulation. Do this with the new DRM client callback acquire_outputs,
so that other clients can have their own handling of vga_switcheroo.

There are only four drivers that support vga_switcheroo: amdgpu,
radeon, i915 and nouveau. Update each of them with the new callbacks.
When vga_switcheroo now invokes pre_switch, each DRM driver forwards
to aquire_outputs and lets the DRM clients handle the new outputs.

Tested with radeon on a notebook with Radeon HD 4225 and HD 5430.

Thomas Zimmermann (10):
  drm/edid: Include <linux/fb.h>
  drm/client: Add acquire_outputs callback; implement for fbdev
    emulation
  vga_switcheroo: Add pre_switch callback to client ops
  vga_switcheroo: Add post_switch callback to client ops
  drm/amdgpu: Implement struct vga_switcheroo_client_ops.pre_switch
  drm/i915: Implement vga_switcheroo_client_ops.pre_switch
  drm/nouveau: Implement vga_switcheroo_client_ops.pre_switch
  drm/nouveau: Implement vga_switcheroo_client_ops.post_switch
  drm/radeon: Implement struct vga_switcheroo_client_ops.pre_switch
  vga-switcheroo: Remove unused interfaces

 drivers/gpu/drm/amd/amdgpu/amdgpu_device.c |  9 ++++-
 drivers/gpu/drm/clients/drm_fbdev_client.c | 23 ++++++++----
 drivers/gpu/drm/drm_client_event.c         | 18 ++++++++++
 drivers/gpu/drm/drm_edid.c                 |  1 +
 drivers/gpu/drm/i915/i915_switcheroo.c     | 11 +++++-
 drivers/gpu/drm/nouveau/nouveau_vga.c      | 28 +++++++++------
 drivers/gpu/drm/radeon/radeon_device.c     |  9 ++++-
 drivers/gpu/vga/vga_switcheroo.c           | 41 +++++-----------------
 drivers/video/fbdev/core/fbcon.c           |  8 -----
 include/drm/drm_client.h                   | 14 ++++++++
 include/drm/drm_client_event.h             |  3 ++
 include/linux/vga_switcheroo.h             | 30 +++++++++-------
 12 files changed, 122 insertions(+), 73 deletions(-)


base-commit: cd8abe2554ec7eba16c1d48ab508732bf93534eb
-- 
2.54.0